The techniques and conditions of platypus fish culture should be matched with silver carp in monoculture and mixed culture.

There are two modes of monoculture and mixed culture, but both of them need to be matched with silver carp, which can control the number and growth rate of algae and avoid eutrophication. Density: body length 50-60 cm, body weight 1 kg 80-100 tails / mu, 2-3 kg 40-50 tails / mu, mixed mode 25 cm 50-70 tails / mu, 50-60 cm 20-50 tails / mu. Capture: about 85% can be captured at one time.

Platypus fish appear more and more frequently on our table, and it has become a hot aquatic product in recent years. Many farmers have also begun to enter the platypus fish culture industry. If they want to be successful in the platypus fish culture industry, it is necessary to master mature culture techniques. Let's take a look at the platypus fish culture techniques and conditions.

Culture conditions of platypus fish

1. Platypus has a wide range of temperature adaptability, it is not afraid of low temperature, but also can withstand high temperature. In winter, even if the surface of the water freezes, as long as there is enough dissolved oxygen in the water, the platypus can still live in the water under the ice. In summer, even if the surface water temperature of the culture pond often exceeds 35 °C, the platypus can still grow normally.

2, the breeding site is suggested to choose in WA steep reservoir, the water area of the farm should be large enough, the water depth should be at least 6 meters, the suitable dissolved oxygen should be 6: 9 mg, the ph value should be 7-8.4, the total hardness should be about 20-40mg/L, ammonia nitrogen should be about 0.02-0.06mg/L, nitrite should be about 0.0015-0.01mg/L, and the water quality should be good.

The method of cultivating fish fry

The method of raising seedlings in flume is generally adopted. After coming out of the film, it is cultivated in the flume for 30-40 days, until 3-5 cm into the pond, this process is the key to the survival of fish fry.

The main contents are as follows: 1. The conditional area of the sink is about 10 square meters, either rectangular or circular, without sharp corners, easy to enter and drain, and anti-escape facilities. Good water quality, no pollution, toxicity, need to be filtered and used. Exchange water twice an hour (stop water for half an hour when feeding), water temperature between 16-28 ℃, dissolved oxygen more than 5 mg / L.

2. The stocking density of spoon-nosed Sturgeon fry decreased from 200 fish / square meter to 100 fish / square meter when it grew to 5 centimeters.

3. The opening bait and feeding spoon snout Sturgeon are zooplankton, and the egg yolk can also be used with zooplankton. The best opening bait of spoon-nosed Sturgeon is copepod Cyclops. If you feed Cyclops, you must grasp the release time, so as to prevent Cyclops from breaking the yolk sac of fish fry and causing mass death of fish fry. The appropriate daily feeding times is 4-8 times, and the breeding room should also be fed at night, and the quantity should be slightly surplus. The initial feed should pass through the 60-mesh sieve to screen out large individuals and harmful aquatic insects. In the later stage, the artificial compound food can be eaten after domestication, and the food intake is about 30% of the body weight. Spoon-nosed Sturgeon has extremely poor eyesight and will not take the initiative to look for food.

4. daily management and matters needing attention should be discharged, screen windows should be brushed, detailed records should be made, etc. When the fry grows to 3-5 cm, several abnormal conditions occur, such as gathering at the corner of the sink, fish fry biting and devouring each other, different sizes, and so on. The reasons for these conditions are uneven nutrition and excessive density. In addition, due to lack of nutrition, fish fry will also swallow water bubbles, making the digestive tract expand and bleed until death. 80% of fry deaths are caused by bite and phagocytosis, and about 20% are caused by gastrointestinal congestion. Therefore, fish fry after 3 cm and 5 cm should be put into ponds with balanced and adequate bait and large water body.

Methods of fish fingerling cultivation in ponds

It takes 3 to 4 months for 3cm fry to grow up to 20cm in length and 200g in weight in that year.

1. The pond requires that the water surface is 3000mu, the water depth is 1.52m, and the pond with convenient access and drainage is better, and each pond should be equipped with a 1.5 kilowatt aerator. Before entering the pond, clean the pond with water, use 150 kilograms of quicklime per mu to kill miscellaneous fish, aquatic plants and so on. The temperature of the pool water is 2-37 ℃, and the optimum temperature is 25-32 ℃.

2. One week before entering the pond, fertilizers should be applied to cultivate good water quality. The general fertilizers are manure (400 kg / mu) and chicken and cow manure. 3 days later, soymilk should be sprinkled into the pond with a dosage of 5 kg / mu. Water spray net should be used to fish again before going into the pond to remove tadpoles and sundries. the difference between the water temperature in the pond and the fish container should not exceed ±3 ℃, and the operation should be carried out in the evening.

3. The main way of reasonable sparse culture is monoculture, with a small number of bottom fish and herbivorous fish, not with silver carp and ferocious fish. The stocking density should be 100 tails per mu. In the process of breeding, in addition to fertilizing and cultivating the water body, soybean milk (2 kg / mu), cake meal, floating wheat flour, bran or special pellet bait are also fed, which are always required to keep the water quality fertile, alive, tender and cool.

4. Strengthen the management and persist in patrolling the ponds every day and make a good breeding record.

5. Fish diseases and treatment of fish species over 10 cm and 15 cm are rarely dead, but several cases of parasitic and bacterial diseases have been reported. Because the spoon-nosed Sturgeon is very sensitive to drugs, especially to heavy metal salts, it should be used with caution. Occasionally, fish diseases are mainly nematodes and trematodes, which can be treated with 2 × 10-6  potassium permanganate or less than 75 × 10-6  formalin. Copper sulfate and chlorine-containing drugs are prohibited in the stage of juvenile fish, and the immersion concentration of antibiotics is about 4 × 10 ~ 6. After cultivating a large fish species of 30cm to 40cm, it can be released directly into the reservoir, or it can continue to be cultured in the pond.

Culture techniques of platypus fish

1. Either monoculture or mixed culture is acceptable, mainly mixed culture, and the proportion is determined according to the specific local conditions. General silver carp + herbivorous fish ∶ Sturgeon = 6: 7 ∶ 1, herbivorous fish ∶ silver carp = 1 ∶ 1.5 × 3. No matter monoculture and mixed culture, it is necessary to match silver carp, because silver carp can control the number and growth rate of algae and avoid eutrophication.

2. Stocking density

① monoculture. When the body length is 50 cm and 60 cm and the weight is 1 kg, there are 100 tails per mu and 40 tails per mu at 2 kg and 3 kg.

② mixed culture. When the body length is 25 cm, it is 50 to 70 per mu, and at the end of the year it grows to 1 kg; when the body length is 50 to 60 cm, it is 20 to 50 per mu, and at the end of the year it grows to 2 to 3 kg. 7-8 per mu in the third year. Adult fish culture in ponds is not suitable for mixed culture in small areas or intensive high-yield ponds, because high yield, high density, ups and downs of dissolved oxygen and rotation are very disadvantageous to spoon Sturgeon.

3. The starting rate of adult fishing is relatively high, and 85% can be caught at one time by pulling the net.

The market prospect of raising duck-billed fish

In the past, the industry knew little about platypus fish, but as the breeding technology gradually matured, the supply of artificial seedlings increased, the breeding scale of platypus fish began to expand gradually in recent years, and platypus fish gradually became familiar to more farmers and consumers. Platypus fish spawn only in March and April every year, and the breeding period is relatively short. If the weather is good, about 15 days. Limited by the number of parent fish and short breeding period, so the supply of seedlings is relatively tight.

At present, duckbill fish culture in China is mainly concentrated in Guangdong, but not in other provinces. With the increasing supply of artificial seedlings and market demand, intensive pond culture and mixed culture of platypus fish are developing rapidly in the Pearl River Delta region, and reservoir cage culture is also increasing.

Although the platypus fish is now slowly known to everyone, and its demand is slowly increasing compared to before, there is still a lot of room for development in its market, and there are still many people who have never eaten duckbill fish. I don't know anything about it. Therefore, the market prospect of platypus fish is very large, it may still have a lot of blank space.